(Haloneocarbyl-substituted)(aliphatic or oxyaliphatic)(halogenated aliphatic or oxyaliphatic)-phosphorates with polyurethanes

ABSTRACT

Included are the title phosphorate compounds, and a process to prepare them comprising contacting a carbylphosphorate mono acid halide with a carbyloxide. For example, ((2-(3-bromo-2,2-bis(bromomethyl)propoxy)ethyl(chloroethyl)-(ethyl))phosphorate can be prepared with (2-(3-bromo-2,2-bis(bromomethyl)propoxy)ethyl)(ethyl)-chloridophosphorate and ethylene oxide. The compounds are useful so-called flame-retardants for polyurethanes, especially flexible foams because, for example, substantially non-scorching and non-odoriferous flame-retardant flexible foams can be readily prepared with the compounds.

This is a divisional of application Ser. No. 895,541, filed Aug. 11,1986, now U.S. Pat. No. 4,851,559.

FIELD

The invention concerns organic phosphorous compounds, their preparationand use. The use particularly concerns flame-retarding compositions suchas polyurethanes, for example, flexible foams, which are usefulstructural materials, for example, in insulating and upholsterycushioning.

BACKGROUND

Carpenter et al., U.S. Pat. No. 3,324,205 (1967), discloses certainchlorinated or brominated quaternary carbon moiety-containingphosphates. These phosphates are disclosed to be useful for impartingflame-resistance to certain normally flammable organic materials.

A problem in the art is production of highly marketable polyurethanes,particularly flexible foams and especially as slabstock. Therein,scorch, odor, processability and flame-retardant efficiency are amongproduction characteristics often needing improvement.

SUMMARY

The invention, in one aspect, is a novel(haloneocarbyl-substituted)(aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorate. Another aspect is a process toprepare said phosphorate comprising contacting a carbylphosphorate monoacid halide with a carbyloxide under conditions whereby said phosphorateis prepared. Still another aspect is a use of said phosphorate in amethod for satisfying a production characteristic of a flame-retardantpolyurethane comprising incorporating said phosphorate into polyurethaneunder conditions whereby said characteristic is satisfied. A furtheraspect is a process to prepare a flame-retardant polyurethane comprisingreacting a polyahl with an organic isocyanate in the presence of saidphosphorate. An additional aspect is flame-retardant polyurethaneshaving said phosphorate incorporated therewith.

These phosphorates can be simply and efficiently prepared. The use ofsaid phosphorate can greatly improve procedures for preparingflame-retardant polyurethanes and thus may greatly improve theirmarketability. Significantly, for example, essentially non-scorchingflame-retardant flexible polyurethane foams, especially as slabstock,can be prepared. And, flame-retardant polyurethanes which areessentially non-odoriferous can be thus prepared.

ILLUSTRATIVE EMBODIMENTS

The (haloneocarbyl-substituted)(aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorate is a tris(organic)phosphorate. Thethree organic moieties are apportioned among onehaloneocarbyl-substituted, one aliphatic or oxyaliphatic and onehalogenated aliphatic or halogenated oxyaliphatic, hydrocarbon moiety.

The haloneocarbyl moiety is a halogen-substituted hydrocarbon oroxyhydrocarbon moiety which contains a neocarbyl moiety. The neocarbylmoiety has a quaternary (i.e., 4°) carbon. The 4° carbon is connectableto the phosphorus through aliphatic carbon to carbon or ether linkages.The neocarbyl moiety is connected to the phosphorus through an oxygensuch as in a phosphate ester.

The neocarbyl moiety is more preferably a β-haloneocarbyl moiety. Theβ-haloneocarbyl moiety is a saturated halogen and carbon-containingmoiety which has the 4° carbon bonded directly to a carbon which forms abond connectable to the phosphorus through an oxygen such as in aphosphate ester. The β-haloneocarbyl moiety is preferably haloalkyl.

Connectable herein means directly or indirectly bonded such as bycovalent bonds. Connected herein means directly bonded.

Aliphatic refers to a saturated or unsaturated, nonaromatic hydrocarbonmoiety. Oxyaliphatic refers to an aliphatic moiety having at least oneether linkage therein such as, for example, in an ethoxyethyl moietysuch as can be incorporated by appropriately employing a carbyloxidesuch as 2-ethoxyethanol. The oxygens of the phosphorates are notconsidered an ether linkage. Halogenated aliphatic or oxyaliphaticrefers to an aliphatic or oxyaliphatic moiety having at least onehalogen substituted, one for one, for hydrogen therein such as, forexample, in a 2-chloropropyl-3-(prop-2-en-1-oxy) or2-chloropropyl-3-(2,3-dibromopropoxy) moiety, or isomeric mixturethereof such as can be incorporated by appropriately employing acarbyloxide such as allyl glycidyl ether, optionally halogenatingafterward.

The halogens include fluorine (F), chlorine (Cl), bromine (Br) andiodine (I). Thus, halo moieties include fluoro, chloro, bromo and iodo.Preferred halo moieties are chloro and bromo.

The (haloneocarbyl-substituted)(aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorate is preferably a phosphate ester ofthe general formula ##STR1## wherein

X is separately at each occurrence hydrogen, halo or C₁₋₅ (i.e., from 1to about 5 carbons) alkyl or C₁₋₅ haloalkyl;

Q is separately at each occurrence C₂₋₁₀ (i e., from 2 to about 10carbons) hydrocarbyl, C₃₋₁₀ oxyhydrocarbyl (i.e., ether-substituted),C₃₋₁₀ halohydrocarbyl or C₃₋₁₀ oxyhalohydrocarbyl;

n is an integer from zero to about 5;

R is C₁₋₁₀ aliphatic or oxyaliphatic, preferably C₂₋₁₀ aliphatic oroxyaliphatic, more preferably C₂₋₁₀ alkyl or oxyalkyl;

R' is C₂₋₁₀ haloaliphatic or oxyhaloaliphatic; but

Q or X contains at least one halo moiety.

Preferably therein,

X is in at least one occurrence a halo moiety, and the remaining X ishydrogen, halo or C₁₋₅ haloalkyl, preferably hydro (H) or halo;

Q is C₂₋₄ alkyl or C₃₋₄ haloalkyl; n is from zero to 2, preferably zero;

R is C₂₋₅ alkyl; and

R' is C₂₋₆ haloalkyl, more preferably C₂₋₄ monohaloalkyl ordihalopropyl.

More preferred haloneocarbyl moieties include those such as ((CH₂ Br)₂CH₂ Cl)CCH₂ --OQ--_(n) ; (CH₂ Br(CH₂)₂)CCH₂ --OQ--_(n) ; (CH₂ Br)₃ CCH₂--OQ--_(n) ; (CH₂ Cl)₃ CCH₂ --OQ--_(n) ; ((CH₂ Br)₂ CH₂ F)CCH₂--OQ--_(n) ; ((CH₂ Br)₂ CCH₂ --OQ--_(n) ; (CH₂ Br(CH₂ Cl)(CH₃))CH₂--OQ--_(n) ; ((CH₂ Br)₂ C₂ H₄ Br)CCH₂ --OQ--_(n) ; ((CH₂ Br)₂ C₂ H₄Cl)-CCH₂ --OQ--_(n) : (CH₂ Br(CH₂ Cl)(C₂ H₄ Br))CCH₂ --OQ--_(n) ; ((CH₂Br)₂ c₂ H₄ F)CCH₂ --OQ--_(n) ; and ((CH₂ Br)₂ C₂ H₅)CCH₂ --OQ--_(n).Most preferred haloneocarbyl moieties are those such as ((CH₂ Br)₂ CH₂Cl)CCH₂ --OQ--_(n) ; (CH₂ Br(CH₂ Cl)₂)CCH₂ -- OQ--_(n) ; (CH₂ Br)₃ CCH₂--OQ--_(n) and (CH₂ Cl)₃ CCH₂ --OQ--_(n), especially ((CH₂ Br)₂ CH₂Cl)-CCH₂ --OQ--_(n).

More preferred Q moieties include those such as C₂ H₃ (CH₂ Cl); C₃ H₅Cl; c₂ H₃(CH₂ Br); C₃ H₅ Br; C₂ H₃ (CH₂ F); C₃ H₅ F; C₂ H₄ and C₂ H₃(CH₃). Most preferred are Q moieties such as C₂ H₃ (CH₂ Cl); C₃ H₅ Cl;C₂ H₃ (CH₂ Br) and C₃ H₅ Br, especially C₂ H₃ (CH₂ Cl) or C₂ H₃ (CH₂ Br)in combination with C₃ H₅ Cl or C₃ H₅ Br (n=2) as (C₂ H₃ (CH₂Cl)--)--(C₃ H₅ Cl); (C₂ H₃ (CH₂ Br)--O--(C₃ H₅ Cl); (C₂ H₃ (CH₂cl)--O--(C₃ H₅ Br); and (C₂ H₃ (CH₂ Br)--O--C₃ H₅ Br), particularly theQ moiety (C₂ H₃ (CH₂ Cl)--O--C₃ H₅ Cl).

However, n is more preferably zero. Thus, most especially preferredhaloneocarbyl moieties include those such as3-chloro-2,2-bis(bromomethyl)propyl;3-bromo-2,2-bis(chloromethyl)propyl; 3-bromo-2,2-bis(bromomethyl)propyl;3-chloro-2,2-bis (chloromethyl)propyl;3-fluoro-2,2-bis(bromomethyl)propyl and 2,2-bis(bromomethyl)propyl,particularly 3-chloro-2,2-bis(bromomethyl)propyl;3-bromo-2,2-bis(bromomethyl)propyl and such as(2-(3-bromo-2,2-bis(bromomethyl)propoxy)ethoxy)ethyl.

More preferred R moieties include C₂₋₄ alkyl, that is, ethyl; propyl andbutyl. Most preferred are C₂₋₄ n-alkyl, that is, ethyl; n-propyl andn-butyl.

The more preferred R' moieties include the C₂₋₄ monohaloalkyl and C₃dihaloalkyl, that is, dihalopropyl. These moieties include for example,2-chloroethyl; 2-bromoethyl; etc. and 1,3-dichloropropyl;1,2-dichloromethylethyl; 3-bromo-1-chloropropyl;1-bromo-2-chloromethylethyl and so forth.

Thus, preferred (haloneocarbyl-substituted)(aliphatic oroxyaliphatic)(halogenated aliphatic or oxyaliphatic)phosphorates includethose such as, for example, ((3-bromo-2,2-bis(methyl)(2-chloroethyl)(ethyl))phosphorate and ((3-bromo-2,2-bis(bromomethyl))(2,3-dichloropropyl)(n-butyl))phosphorate, however, themost preferred are ((3-chloro-2,2-bis(bromomethyl)(2-chloroethyl)(ethyl))phosphorate;((3-bromo-2,2-bis(bromomethyl)propyl)-(2-chloroethyl)(ethyl))phosphorate; ((2-(3-bromo-2,2-bis(bromomethyl)propoxy)ethoxyethyl)(2-chloroethyl)(ethyl))phosphorate and((3-bromo-2,2-bis(bromomethyl)propyl)(2,3-dichloropropyl)(ethyl))phosphorate.

The (haloneocarbyl-substituted)(aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorate can be prepared by the process toprepare said phosphorate comprising contacting a carbylphosphorate monoacid halide with a carbyloxide. Conditions are those sufficient toprepare said phosphorate.

The carbylphosphorate mono acid halide is an organic phosphorate whichhas one of the organic ester moieties substituted with a halide,preferably selected from the group consisting of fluorido, chlorido andbromido. More preferably, the halide of the carbylphosphorate mono acidhalide is selected from the group consisting of chlorido and bromido.

Preferably, the carbylphosphorate mono acid halide is of the generalformula ##STR2## wherein

X' is separately at each occurrence F, Cl or Br, preferably Cl or Br,more preferably Cl;

Z is appropriately selected from the haloneocarbyl moiety or thealiphatic or oxyaliphatic moieties, preferably the foregoing ##STR3## orR moieties; and

Z' is such as Z, provided that Z' and Z are not of the same genera ofmoieties; for example, with Z haloneocarbyl, Z' can be either the(aliphatic or oxyaliphatic) moiety or the (halogenated aliphatic oroxyaliphatic) moiety.

The carbylphosphorate mono acid halide can be obtained or prepared byknown procedures or by a procedure such as disclosed herein. Forexample, the carbylphosphorate acid halide can be prepared by reacting aphosphorus trihalide such as, for example, phosphorus trifluoride;phosphorus trichloride; phosphorus tribromide with the appropriatemonohydroxy alcohols which correspond to the haloneocarbyl or alternatemoieties, for example, the aliphatic hydrocarbyl moieties to be bound tothe phosphorus as phosphate ester. See, for example, copending U.S.patent application Ser. No. 843,452, filed Mar. 24, 1986 (AttorneyDocket No. C-34,970) (incorporated herein by reference). Or, thecarbylphosphorate mono acid halide can be prepared by halogenating theappropriate corresponding tris(organic)phosphite. This halogenation canbe carried out with halogenating agents such as, for example, elementalfluorine, chlorine, bromine and iodine and bromine chloride, preferably,chlorine and bromine.

The carbyloxide is an oxygen-containing organic compound whichappropriately corresponds to the remaining haloneocarbyl, the required(aliphatic or oxyaliphatic) or the (halogenated aliphatic oroxyaliphatic) moieties or suitable parts thereof. Suitable carbyloxidesinclude

monohydroxyl alcohols (preferably contacted with the carbylphosphorateacid halide in the presence of an acid acceptor), especially of thegeneral formula ROH with R as defined herein;

oxetanes (preferably contacted with the carbylphosphorate acid halide inthe presence of a Lewis acid catalyst) such as, for example,3-bromoethyl-3-methyloxetane, 3-bromomethyl-3-ethyloxetane, 3,3-bis(chloromethyl)oxetane, 3-(chloromethyl)-3-methyloxetane; and

oxiranes, for example, ethylene oxide; 1,2-propylene oxide;epichlorohydrin; epibromohydrin, including neocarbyl-containing oxiranessuch as of the general formula ##STR4## wherein Q and X are as definedherein; n' is an integer from zero to 4, preferably 1. Theneocarbyl-containing oxiranes can be prepared by a procedure such asthat disclosed by Gibbons, U.S. Pat. No. 3,784,500 (1974) (incorporatedherein by reference). The oxiranes are also preferably contacted withthe carbylphosphorate acid halide in the presence of the Lewis acidcatalyst.

In general, in preparing the (haloneocarbyl-substituted) (aliphatic oroxyaliphatic)(halogenated aliphatic or oxyaliphatic)phosphorate, thecarbylphosphorate mono acid halide to carbyloxide equivalent ratio cancorrespond roughly to a 1:1 equivalent ratio. The ratio is based on thenumber of equivalents of acid halide in the carbylphosphorate mono acidhalide.

Temperatures, in general, can be those employed with the preparation ofother organic phosphate esters. Temperatures are preferably from about-10° C. (minus 10° C.) to about 120° C. Initial contact is preferablycarried out at cooler temperatures such as about normal roomtemperature, for example, 25° C., or below. Extended contact time, ifdesired or necessary, is preferably carried out at elevated temperaturessuch as about 30° C. or above.

Pressures, in general, can be those employed with the preparation ofother organic phosphate esters (phosphorates). Preferably, the pressureis ambient pressure.

Times (duration) are those which are sufficient to carry out thepreparation. Typical times can be the time it takes for the initialcontact to an extended time such as 100 hours or more. Preferably, thetime is extended beyond the initial contact for about 1 to 20 hours.

The acid acceptor employed in conjunction with the alcohols can be acompound such as, for example, pyridine, triethylamine or sodiumcarbonate. The acid acceptor can be added in the appropriate incrementsto thus accept acid produced by reaction with the carbylphosphorate monoacid halide.

The Lewis acid catalyst employed in conjunction with theneocarbyl-containing oxiranes and oxetanes is preferably a compound suchas aluminum tribromide, aluminum trichloride or titanium tetrachloride.Boron trifluoride etherate (BF₃ -et) is also preferred. For the mostpart, the Lewis acid catalysts can be employed in amounts from about1/10 to about 5 percent by weight based on the weight of thecarbylphosphorate mono acid halide.

The reaction can be run neat or can employ a diluent. Preferably, aliquid diluent is employed. Preferred liquid diluents includehalogenated alkanes such as, for example, methylene chloride,chloroform, carbon tetrachloride and 1,2-dichloroethane.

Preferably, the phosphorates of the invention are prepared by thesequence of the reactions as follows: a neopentyl alcohol such as, forexample, 3-chloro-2,2-bis(bromomethyl)propanol;3-bromo-2,2-bis(bromomethyl)propanol or 3-bromo-2,2-dimethylpropanol isreacted with a phosphorus trihalide, for example phosphorus trichloride,liberating hydrogen halide (e.g., HCl). Next, the resultingdihalophosphite derivative is reacted with an oxirane such as, forexample, ethylene oxide, propylene oxide or epichlorohydrin to produce aphosphite. The phosphite is halogenated, for example, chlorinated, at10° C. or colder to produce a halophosphorate, for example, achlorophosphorate, liberating additionally halogenated organic compoundcorresponding to the now halogenated moiety released from the phosphite(e.g., 1,2-dichloroethane). This latter general phosphorus compoundproduct is next reacted with an alcohol such as, for example, methanol;ethanol or propanol, preferably ethanol or propanol, in the presence ofthe acid acceptor, for example, pyridine, triethylamine or potassiumcarbonate, to produce the desired phosphorate.

Another preferred method for the preparation of these derivatives is thesequence reaction of the neopentyl alcohols previously mentioned with anoxirane in the presence of BF₃ -etherate. Oxiranes such as ethyleneoxide, propylene oxide, epichlorohydrin or allyl glycidyl ether (whichis later halogenated) or combination of these are most preferred. Moleratios are 1 to 4, based on the alcohol. This resulting product is nextreacted with phosphites such as trimethyl phosphite, triethyl phosphiteor tributyl phosphite, most preferably triethyl phosphite eachliberating an alcohol. The resulting product is next halogenated, forexample, chlorinated, at 10° C. or lower, liberating halogenatedorganic, for example, 1-chloroethane, and the resulting product isreacted with an oxirane such as those mentioned above in the presence ofa Lewis acid catalyst such as TiCl₄ or AlCl₃ to produce the desiredproduct.

The (haloneocarbyl-substituted)(aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorate is preferably purified byprocedures generally analogous to those in Birum et al., U.S. Pat. No.3,132,169 (1964) (incorporated herein by reference), for example, by aneutral or basic aqueous wash of the (halo-neocarbyl-substituted)(aliphatic or oxyaliphatic) (halogenated aliphaticor oxyaliphatic)phosphorate product. A dilute acid wash of the productcan be employed, preferably with an aqueous mixture of the acid,especially with employment of catalysts such as AlCl₃. The dilute acidwash is a most preferred step. The product mixture ratio is typicallynot changed by the dilute acid wash. Purification by distillation is anadditionally preferred step.

The process can prepare an extremely pure product which contains littleor no undesired phosphorate by-products. Preferably, the desired(haloneocarbyl-substituted)(aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorate is 90 percent free of otherphosphorate by-products, or more pure, as determined by gaschromatographic methods (e.g., capillary), more preferably about 95percent or more pure, and most preferably, 99 percent or more pure.

The (haloneocarbyl-substituted)(aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorate may be a low viscosity liquid suchas is indicated by Brookfield viscosity. The Brookfield viscosity hereinis the viscosity measured at 25° C. on a Brookfield viscometer with anumber 6 spindle rotating at 100 rotations per minute (rpm) submersedwith sample in the center of a sample vessel with a width at least 125percent of the spindle diameter.

Preferably, the Brookfield viscosity of the(haloneocarbyl-substituted)(aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorate product is about 10,000 centipoise(cP) or below at 25° C., more preferably about 5,000 cP or below andmost preferably about 2,500 cP or below. It is especially preferred thatthe Brookfield viscosity of the product at 25° C. is about 1,000 cP orbelow.

Preferably, the (haloneocarbyl-substituted)(aliphatic oroxyaliphatic)(halogenated aliphatic or oxyaliphatic)phosphorate has highthermal stability. One preferred method to measure this is bythermogravimetric analysis (i.e., TGA), where the sample tested iscontinuously monitored for weight loss as its temperature isprogressively increased in an oven with a nitrogen atmosphere. Theprogressive temperature increase is at a rate of 20° C. per minute froman intitial temperature of 20° C. with the sample size initially between0.010 g and 0.020 g. Under these test conditions, thermogravimetricanalyses preferably have a 50 percent weight loss of sample (TGA₅₀) at atemperature of about 200° C. or above, more preferably about 230° C. orabove and most preferably about 250° C. or above.

The thermogravimetric analysis at 10 percent weight loss (TGA₁₀) can beused also. The TGA₁₀ is otherwise measured as is the TGA₅₀. PreferredTGA₁₀ values include values found at about 160° C. or above, morepreferably about 180° C. or above and most preferably about 200° C. orabove.

In general, the (haloneocarbyl-substituted) (aliphatic oroxyaliphatic)(halogenated aliphatic or oxyaliphatic)phosphorate can beemployed as a component in flame-retardant polurethanes. Amounts thusemployed are preferably those sufficient to render the polyurethaneflame-retardant, such as in amounts from about 1/2 to 50 percent byweight of other polyurethane components, for example, in amounts fromabout 5 to 20 percent by weight of polyahl of a foam. The use cantypically satisfy at least one production characteristic of thepolyurethanes.

The polyurethanes of this invention comprise organic polyisocyanates,polyahls and flame-retardant amounts of the phosphorate compounds ofthis invention. The polyahls are organic compounds with at least twoactive hydrogen moieties such as determined by the Zerewitinoff test(see, e.g., Kohler et al., J. Am. Chem. Soc., 49, 3181-88 (1927)) andwith an average molecular weight of at least about 60 g per mole. See,for example, Rosenkranz et al., U.S. Pat. No. 3,928,299 (1975)(incorporated herein by reference) for compounds otherwise known whichmay thus be considered polyahls. The polyurethanes can be prepared byknown methods such as disclosed by Hoppe et al., U.S. Pat. No. Re 24,514(reissued 1958) (incorporated herein by reference). The foams may alsobe prepared by the froth technique as described by Dunlap et al. in U.S.Pat. No. 3,755,212 (1973); by Barron et al. in U.S. Pat. No. 3,821,130(1974); and by Walters et al. in U.S. Pat. No. 3,849,146 (1974) whichare also incorporated herein by reference. The most preferred techniqueis the "one-shot" technique, where all the reactants are addedsimultaneously at the time of foaming, because it is generally used toprepare flexible polyurethane foams. Most, if not all, modern flexibleslabstock (continuous) polyurethane foam machines are designed on thebasis of this approach.

Of the polyahls, polyols are preferred. Preferred polyols include triolpolyether polyols with equivalent weights from about 500 to 2,500 andblends of triols and diols with overall active hydrogen functionality offrom about 21/2 to 3. See, for example, Baggett et al., U.S. Pat. No.2,871,219 (1959); Smith, U.S. Pat. No. 2,891,073 (1959); Pannell, U.S.Pat. No. 3,058,921 (1962) (each incorporated herein by reference).

Especially preferred polyisocyanates include a mixture of 80 percent byweight 2,4-toluene diisocyanate with 20 percent by weight 2,6-toluenediisocyanate (generally known as TDI 80/20 or T-80) and a mixture of 65percent by weight 2,4-toluene diisocyanate with 35 percent 2,6-toluenediisocyanate (TDI 65/35 or T-65). These are typically used in flexiblepolyurethane foams. The TDI 80/20 is more preferred.

Also preferred are pure and polymericmethylene-4,4'-diphenyldiisocyanate (MDI). The MDI types are typicallyused in rigid polyurethane foams.

Other components can be present in the preparation of the polyurethanes,especially the foams, as is generally known in the art. For example,catalysts such as nitrogenous catalysts such as amino compounds, forexample, those disclosed by McEntire, U.S. Pat. No. 4,101,470 (1978);Zimmerman et al., U.S. Pat. No. 4,433,170 (1984); Jachimowicz, U.S. Pat.No. 4,450,246 and Zimmerman et al., U.S. Pat. No. 4,464,488 (1984) (eachincorporated herein by reference) can be employed with other catalystssuch as tin compounds including those such as stannous chloride and tinsalts of carboxylic acids such as, for example, stannous octoate anddibutyltin di-2-ethylhexanoate, as well as other organometalliccompounds such as disclosed by Brachhagen et al., U.S. Pat. No.2,846,408 (1958) (incorporated herein by reference). Also, a wettingagent or surface-active agent can be employed, especially in preparinghigh grade foams, preferably a silicone containing organic compound orblock polyethers of propylene glycol prepared with ethylene oxide andpropylene oxide. Also, a chain-extending agent, which is a compound withat least two active hydrogens per molecule such as, for example,1,2-diaminoethane; (R)-1,2-dimethylaminopropane; 2-aminoethanol;ethylene glycol; L-alanine and preferably water can be employed. Also,especially in the preparation of the foamed polyurethanes, an auxiliaryblowing agent preferably such as a volatile haloalkane, for example,trichlorofluoromethane, can be employed.

Preferred flexible polyurethane foam formulations with which the(haloneocarbyl-substituted)(aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorates are incorporated as a flameretardant include compositions such as follows:

    ______________________________________                                                          Concentration                                               Reactant          (pph)                                                       ______________________________________                                        polyol            100                                                         TDI index         80-120                                                      flame retardant   6-18                                                        water             1.0-5.5                                                     silicone surfactant                                                                             0.2-3                                                       tertiary amine catalyst                                                                         0.02-2                                                      auxiliary blowing agent                                                                         0.5-40                                                      tin catalyst      0.05-0.5                                                    ______________________________________                                    

Also, flexible foams with densities from about 1.0 pound per cubic foot(i.e., about 16 kg per m³) to about 4.0 pounds per cubic foot (i.e.,about 64 kg per m³) are preferred.

The polyurethane production characteristic(s) which is (are) satisfied,or even improved, by the method of this invention, is preferablyselected from the group consisting of

(1) processability;

(2) scorch;

(3) odor; and

(4) flame-retardant efficiency.

Processability is a production characteristic which can be satisfied orimproved. A preferred measure of the processability is the Brookfieldviscosity.

Processability difficulties for higher viscosity flame-retardantcompounds may be reduced by the use of diluents such as non-halogenatedphosphate ester compounds. Preferably, such diluents are not used inprocessing.

Scorch is a production characteristic which may be satisfied or improvedby being reduced to minimal levels or even eliminated. A preferredmeasure of scorch (discoloration) is a ΔE in National Bureau ofStandards (i.e., NBS) units by the Hunter Colorimeter test of about 10or below, more preferably about 6 or below and most preferably about 4or below, or, particularly in a laboratory scale test, after inducingscorch by the Wampfler-Fielding procedure described in U.S. patentapplication Ser. No. 856,523, filed Apr. 28, 1986 (Attorney Docket No.C-35,122) (incorporated herein by reference), comparable Hunter test ΔEvalues of about 20 or below; 10 or below; 8 or below.

The Hunter test differs from the known Gardner Colorimeter test in thatin the Hunter test, the color of both the sample set and control set arecompared to the color of a standard pure white tile. The standard whitetile may contain pure white MgO. If the sample versus control differenceis determined by subtraction (i.e., sample-control) after thiscomparison to the tile, the values of the Hunter test are typicallysubstantially equivalent to values determined by the Gardner test. TheGardner Colorimeter test is more completely described in Albright etal., U.S. Pat. No. 4,083,825 (1978) from column 8, line 58 to column 11,line 23 (which material is incorporated herein by reference).

The most preferred polyurethane foam sample for the Hunter Colorimetertest, especially with flexible foams, is a representative sample takenfrom a large-scale commercial production bun. The bun is cross-sectionedand the whole large-scale cross-section of bun is tested for scorch inthe minimum number of required 4.0 square-inch (26 cm²) cross-sections(2.0 inches×2.0 inches; 5.1 cm×5.1 cm), and each smaller-scale ΔE valueis summed, and the summation is divided by the required number of 4.0square-inch cross-sections. This is the average ΔE value of thelarge-scale sample. The sample is 2.0 inches (2.5 cm) in height. Thus,the sample is a cube of 2.0 inches per side.

As an indicia of scorch resistance when incorporated into apolyurethane, especially in a flexible foam, the thermal stabilityproperties of the phosphorate flame-retardant compounds may be used.

Odor is a production characteristic which may be satisfied or improvedby being reduced or even eliminated. The presence of a halogenatedneopentane, for example, tetrabromoneopentene, at levels of about 1-4percent by weight, may cause the odor. Keeping the presence of such ahalogenated neopentane to levels below 1 percent by weight, morepreferably 0.5 percent by weight, typically eliminates such an odor inthe resulting flame-retardant polyurethane, especially in slabstockfoam. The instant process typically does not produce such an odoriferoushalogenated neopentane.

Flame-retardant efficiency is a production characteristic which may besatisfied or improved. By flame-retardant it is meant that thephosphorate, when incorporated into the polyurethane, reduces thepropensity of the polyurethane to propagate combustion after the removalof a small-scale ignition source such as a lit Bunsen burner. Theflame-retardant efficiency in additive-type flame-retardant phosphoruscompounds incorporated with polyurethanes is typically a function ofphosphorus-halogen content. Broiminated compounds are preferred. Ahigher bromine content increases the flame-retardant efficiency by itsmere presence within the composition. Also, thus, the lower alkyl estercompounds are preferred. The C₂₋₄ alkyl esters are most preferredbecause the methyl ester has a tendency to hydrolyze more easily andthus cause a humid aging problem.

One preferred method to measure this flame-retardant efficiency is anoxygen index (i.e., limiting oxygen index) measured by the oxygen demandtest of ANSI/ASTM D-2863-77 (ASTM American National Standard) whereinthe minimum concentration of oxygen in a mixture of dry O₂ and dry N₂flowing upward, needed to cause combustion in a standard test columnthat will just support combustion under equilibrium conditions ofcandle-like burning is measured. Other conditions of the ANSI/ASTMD-2863-77 oxygen demand test include those set out in the ASTM AmericanNational Standard test (incorporated herein by reference).

Preferably, for ten appropriate A through D type (as in the D-2863-77standard) specimens with the flame-retardant composition, the averagelimiting oxygen index (i.e., average LOI) is raised 10 percent or more,more preferably 20 percent or more and most preferably 30 percent ormore, when measured either by time until extinguishing of the flame ordistance of the burned specimen according to ASTM D-2863-77, whencompared to ten otherwise comparable specimens without theflame-retardant composition. It is also preferred that the average LOIof ten appropriate A through D type specimens is raised to above 21,more preferably to about 25 or above and most preferably, to about 30 orabove.

When incorporated into a rigid polyurethane foam, such as an insulatingfoam, preferred measures include the Steiner tunnel test of ASTM E-84 orthe equivalent such as Underwriter's Laboratories 723. It is preferredthat the rigid foam pass the E-84 test or equivalent with a Class IIrating or better. It may be desired to incorporate into theflame-retardant composition an amount effective to secure a Class Irating. Other tests such as the German DIN-4102-B2 test or its Swisscounterpart may be used.

When incorporated into a flexible polyurethane foam as a flameretardant, a preferred measure of the flame-retardant efficiency of theflame-retardant foam composition is the two-part California 117 test(i.e., both of the Vertical Burn tests and the Smoldering test) as inCalifornia Technical Bulletin 117, State of California Department ofConsumer Affairs Bureau of Home Furnishings, North Highlands, California(January, 1980) (which is incorporated herein by reference). It ispreferred that the two-part California 117 test is passed by theflame-retardant flexible foam composition.

In each of the foregoing, it is preferred that the flame-retardantefficiency be substantially retained after aging. A preferred measure ofthis retention may be obtained by subjecting the flame-retardantpolyurethane to elevated temperature (e.g., 104° C.) aging in acirculating air oven for 24 hours, followed by passing the requirementsof the foregoing flame-retardant efficiency tests, such as in the caseof a flexible foam by passing the California 117 Vertical Burn test.

Reduction of scorch and odor are each, and especially in combination, ofhigh priority. Reduction of problems due to odor and processability orscorch and processability are also desirable. Reduction of each of theproblems due to processability, scorch, odor and loss of flame-retardantefficiency is most desired.

Preferably, the method of employing the(haloneopentyl-substituted)(aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorate as a flame retardant is generallyakin to the method disclosed in the referenced copending U.S. patentapplication Ser. No. 856,523, filed Apr. 28, 1986.

Specific Embodiments

The following examples further illustrate the invention. Parts andpercentages are by weight unless otherwise specified.

EXAMPLE 1

Preparation of phosphoric acid: ethyl, chloroethyl,(2-(3-bromo-2,2-bis(bromomethyl)propoxy)ethyl)ester of the followinggeneral formula (E4) by the following general sequence ##STR5##

A. Preparation of the mono acid halide

Into a flask are placed 65.5 g of 3-bromo-2,2-bis(bromomethyl)propanol(0.2 mole), 200 ml of methylene chloride and 1 ml of BF₃ -et. Thismixture is stirred until a solution is obtained. A solution of 8.8 g ofethylene oxide (0.2 mole) in 25 ml of methylene chloride is addeddropwise. Upon completion of reaction, 5 g of sodium carbonate is added,and the mixture is stirred. The insoluble matter is filtered off, andthe liquid phase is heated to 80° C. at 1-2 mm Hg (0.133-0.266 kPa)until low boilers cease to distill off. The mixture is allowed to cool,and 36 g of triethyl phosphite and 2 g of sodium ethylate are added.This mixture is stirred and is slowly heated to 120° C. while the lowboiling by-product, ethanol, distills off. At the time ethanol ceases todistill off, the reaction mixture is placed under reduced pressure andis allowed to cool. The resulting oil containing E2 is taken up in 200ml of methylene chloride and is cooled to 10° C. in an ice water bath.Next, 16 g of chlorine is bubbled into the reaction mixture. Next, themixture is stirred until completion of reaction as is indicated byabsence of chlorine color. The mixture contains E3.

B. Preparation of the title phosphate (E4)

Next, 1 g of AlCl₃ is added, and a solution of 10 g ethylene oxide in 50ml of methylene chloride is added dropwise. Upon completion of thisaddition, the mixture is heated to reflux for 30 minutes, and some ofthe low boilers are distilled off. The mixture is allowed to cool, and100 g of dilute (1N) aqueous HCl solution is added. The product phase isseparated and is stirred with another 100 ml of the dilute HCl, isseparated, is stirred with a mixture of 5 g of sodium carbonate and 30 gof sodium sulfate, is filtered, and solvent is distilled off at 80° C.and under 1-2 mm Hg pressure to produce 79 g of an oil (73 percentyield). The oil has a Brookfield viscosity (No. 6 spindle; 100 rpm; 25°C.) of 750 cP and a TGA₁₀ of 202° C.; TGA₅₀ of 256° C.

EXAMPLE 2

Preparation, scorch inducement and evaluation of flexible polyurethanefoams

A. Preparation

If a flexible polyurethane foam is prepared as follows, the foam has anisocyanate index of 110.

First, the A-side (isocyanate side) is weighed out into a half-cup (118ml) glass jar and set aside. The A-side is 62.3 g of Voranate* T-80(*Trademark of The Dow Chemical Company), a mixture of toluene-2,4- and2,6-diisocyanates in a weight ratio of toluene-2,4-diisocyanate totoluene-2,6-diisocyanate of about 80:20.

Next, the B-side (polyahl side) is weighed out and is placed, in thenumerical sequence listed, into a one-quart (946 ml) paper cup setbeside the set aside A-side.

    ______________________________________                                                                (g)                                                   B-Side Component        Weight                                                ______________________________________                                        Voranol* 3137 (*Trademark of The Dow                                                                  100.0                                                 Chemical Co.) (a polyether polyol                                             with a hydroxyl number of about                                               53.4)                                                                         Sample FR               10.0                                                  (phosphorate separately of Example                                            1 or Thermolin ® (Olin Chemical                                           Co.) (comparative))                                                           Water                   5.0                                                   Q-25125                 1.0                                                   (silicone surfactant available                                                from The Dow Corning Corp.)                                                   Methylene chloride      6.0                                                   NIAX ™ A200 (amine catalyst                                                                         0.30                                                 available from Union Carbide)                                                 T-10 (50% solution of stannous                                                                         0.60                                                 octoate available from M&T                                                    Chemical)                                                                     ______________________________________                                    

Next, the B-side is mixed with a high speed electric drill-poweredstirrer for 15 seconds. Next, the A-side is immediately added, andimmediately mixed with the drill-stirrer for 5 seconds.

The A-B mixture is immediately poured into an 83-ounce (2.45-liter)clean cardboard bucket, and the resultant foam is allowed to rise, thebucket being in upright position in an upright 5-gallon (18.9-liter)pail, the bucket disjointed from and above the surface of 1/2 gallon ofwater in the pail.

B. Scorch inducement by the Wampfler-Fielding procedure

Following "blow-off" the lid of the pail containing the water is putinto place and the covered pail containing the bucket is placed in a160° C. oven for one hour. The relative humidity in the covered pail isthus approximately 100 percent. Next, the bucket with foam is removedfrom the pail, and the foam is allowed to cool to room temperature atambient conditions in the bucket.

The foregoing severe conditions are employed to attempt to induce scorchbecause generally humid conditions are a cause of scorch(discoloration), especially in flexible foams and particularly in thosewith phosphorus- or halogen-containing components. The high temperatureand the time duration are employed because of their resemblence to theconditions which can accompany commercial scale production of foamedpolyurethanes, especially flexible slabstock. Overall, the inducedconditions are more severe than typically encountered in polyurethanefoam production.

C. Evaluation

A two-inch (5.08-cm) cross-sectional slice is cut off near the top ofeach foam sample. Next, a two-inch section is cut from the middle ofeach cross-sectional slice. The underside of this section is used forcolor determination.

Color is measured on a Macbeth Colorimeter using the Hunter Color Scale.The Hunter Color Scale compares the color of the sample to a standardwhite tile.

Three measurements are made for each sample and then averaged. Theaverage delta E value (ΔE) for each sample is then compared to theaverage ΔE value determined by the Hunter Color Scale for an otherwiseequivalent foam sample section containing no flame retardant. A value(ΔE(FOAM)) is calculated according to the following equation.

    ΔE(FOAM) =ΔE(SAMPLE)-ΔE(NO FR FOAM)

The following is obtained.

    ______________________________________                                        SAMPLE FR  ΔE           ΔE(FOAM)                                  ______________________________________                                        Example 1  about              about                                           Thermolin ® 101                                                                      18                 11                                              None       7.0                --                                              ______________________________________                                    

The ΔE(FOAM) values as are obtained with the SAMPLE FR of Example 1 arecomparable to or even sometimes better than the value as is obtainedwith the comparative SAMPLE FR. The comparative (Thermolin® 101) istypically sold as a substantially non-scorching flame retardant. Thus,the (haloneocarbyl-substituted)(aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorates are at least substantially, evenessentially, non-scorching flame retardants for polyurethanes.

The foams are flame-retardant. The foam with SAMPLE FR of Example 1generally passes requirements of the California 117 test. The foam withthe SAMPLE FR of Example 1 is at least substantially non-odoriferous.

EXAMPLE 3

Commercial-type production

If, by the one-shot technique, a commercial-type scale slabstockflexible polyurethane foam with about 110 isocyanate index is preparedwith about 10 pph of the phosphorate of Example 1 incorporated therein,the foam is easily processable and is flame-retardant. In addition, thefoam exhibits high flame-retardant efficiency, passing the California117 test as set out by the California 117 test requirements, isessentially non-scorching and is substantially non-odoriferous.

We claim:
 1. A method for satisfying a production characteristic of aflame-retardant polyurethane comprising incorporating a(haloneocarbyl-substituted) (aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorate into a polyurethane whereby saidproduction characteristic is satisfied.
 2. The method of claim 1 whereinsaid production characteristic is selected from the group consisting ofprocessability; scorch; odor and flame-retardant efficiency.
 3. Themethod of claim 2 whereby said production characteristic is improved,and the polyurethane is a flexible slabstock foam.
 4. A process toprepare a flame-retardant polyurethane comprising reacting a polyahlwith an organic isocyanate in the presence of a(haloneocarbyl-substituted)(aliphatic or oxyaliphatic)(halogenatedaliphatic or oxyaliphatic)phosphorate.
 5. The process of claim 4 whereinthe polyurethane is a flexible foam, and said phosphorate is selectedfrom the group consisting of ((2-(3-chloro-2,2-bis(bromomethyl)propoxy)ethyl)(chloroethyl)(ethyl)phosphorate and((2-(3-bromo-2,2-bis(bromomethyl)propoxy)ethyl)(chloroethyl)(ethyl))phosphorate.
 6. Flame-retardant polyurethaneshaving a (haloneocarbyl-substituted)(aliphatic oroxyaliphatic)(halogenated aliphatic or oxyaliphatic)phosphorateincorporated therewith.
 7. The composition of claim 6 which issubstantially non-scorching and non-odoriferous.
 8. The composition ofclaim 7 which is a flexible foam.
 9. The composition of claim 8 which isa slabstock flexible foam.
 10. The composition of claim 8 which passesthe California 117 flame-retardant test.
 11. The composition of claim 9which passes the California 117 flame-retardant test.
 12. Thecomposition of claim 11 wherein said phosphorate is((2-(3-chloro-2,2-bis(bromomethyl)propoxy)ethyl)(chloroethyl)(ethyl))phosphorate and((2-(3-bromo-2,2-bis(bromomethyl)propoxy)ethyl)(chloroethyl)(ethyl))phosphorate.